* Fix truncated normal.

* Fix.

* Make nce support more distribution.

* Fix API.spec.

* Fix python API.

* Fix.
test=develop

* Fix API.spec
test=develop

* Fix sampler.

* Fix order of arguments in python API.
test=develop

* add cudnn ctc loss

* wip add test test=develop

* wip

* wip

* done test=develop

* move include cudnn test=develop

* test test=develop

* fix build test=develop

* fix build test=develop

* fix build on cudnn5 test=develop

* fix cudnn5 build test=develop

* fix cudnn5 build test=develop

* merge develop softmax functor change test=develop

* add selu

* use for range
test=develop

* add API
test=develop

* follow comment
test=develop

* update API.spec
test=develop

test=develop

* Support softmax return in softmax_with_cross_entropy

* Add test for return_softmax=False

test=develop

test=develop

Density prior box operator for image detection model.

* add lod tensor array concat

* add lod tensor array concat

* test=develop

* add lod tensor array concat
test=develop

* Fix API.spec
test=develop

* add lod tensor array concat
test=develop

* revise some bug of lod tensor array concat
test=develop

* add unittest for tensor array concat
test=develop

* change to tensor array to tensor
test=develop

* revise bug
test=develop

* revise a bug
test=develop

* revise a bug
test=develop

* revise a bug of python3
test=develop

* exhaustive search for cuDNN conv.
* Refine code and add unit testing.
* Fix model load in fluid/inference and unit testing in conv2d
* Follow comments.
* Fix compiling test=develop

test=develop

Dry run tests will skip `Op.Run` and just perform job scheduling. It helps to analysis dead lock in PE.

test=develop

This reverts commit ce7d9b07.

* exhaustive search for cuDNN conv.
* Refine code and add unit testing.
* Clean code
* Fix model load in fluid/inference and unit testing in conv2d
* Follow comments.

1. Non utf-8 characters within comments of OPs may lead to protobuf fail to parse_from_string
2. comment out some ops which not supported on windows
3. cuda libs may not be correctly linked to target on windows

test=develop

* remove unnecessary var_and_op
test=develop

* fix _init_zero_idx_
test=develop

test=develop

* Add affine grid generator.

* fix ffine grid.

* Add unitest.

* Add CPU kernel and fix unitest.

* Fix CPU kernel.

* Refine code.
test=develop

* Fix python api.
test=develop

* Update python api.
test=develop

* Fix comment.
test=develop

* Rename affine_grid_generator to affine_grid and enhence unitest.
test=develop

* Fix unitest.
test=develop

test=develop

test=develop